Chenopodium

See list of 16 species in this genus

Size, orientation, surface patterns, and nature of the pericarp (e.g., adherent, loose) are all very important characters of the fruits. Most species of goosefoots have an adherent pericarp that covers the lustrous, often black, seed in fruit. Sometimes the shiny surface of the seed is visible in places where the pericarp has been abraded due to pressing and storage. This is very different from the utricle-type fruit where the pericarp loosens, splits, and small flakes or sheets detach from the seed. Though many species can be confidently identified while in flower, some groups of taxa require mature fruits for determination. Reference: Wahl (1954).

  • 1a. Fruits arranged vertically or both vertically and horizontally in the calyx; calyx with 
3–5 sepals [Fig. 333]
    • 2a. Plants perennial from a thick, woody root system; leaf blades entire except for the basal pair of outwardly pointing lobes; achenes 1.5–2 mm wide; styles persistent on 
the fruit, 0.8–1.5 mm long; calyx with 4 or 5 sepals
    • 2b. Plants annual from a taproot; leaf blades dentate or serrate (sometimes ± entire in 
 C. rubrum var. humile);
      • 3a. Principal leaf blades lanceolate to elliptic or oblong, conspicuously farinose on the abaxial surface; glomerules of flowers 1.8–2.5 mm wide; most fruits horizontally oriented, some vertically oriented [Fig. 333]
      • 3b. Principal leaf blades triangular to rhombic-ovate (rarely oblong), green or sparsely farinose on the abaxial surface; glomerules of flowers 2–12 mm wide; most or all fruits vertically oriented
        • 4a. Glomerules of flowers 2–5 mm wide; sepals at maturity herbaceous (somewhat fleshy in var. humile); horizontal seeds frequently present; vertical seeds with a basal radicle; plants coastal halophytes
        • 4b. Glomerules of flowers (3–) 5–12 mm wide; sepals at maturity fleshy; fruits all vertically oriented; horizontal seeds absent; vertical seeds with an apical radicle; plants inland weeds of forest openings and disturbed areas
          • 5a. Glomerules without subtending bracteal leaves (except sometimes the lower ones of each branch); seeds with convex sides, not grooved around periphery; flowers maturing from apex of inflorescence toward base
          • 5b. Glomerules subtended by bracts; seeds with a flattened groove around the periphery; flowers maturing from base of inflorescence toward apex
  • 1b. Fruits arranged horizontally in the calyx; calyx with 5 sepals [Figs. 328,334,335]
    • 6a. Sepals flat or with an inconspicuous keel on the abaxial surface, at maturity conforming to the outline of the fruit and the outline of the calyx appearing ± circular (except where individual sepals spread or reflex away from fruit) [Fig. 334]; stems, leaf blades, and sepals usually glabrous and green (plants sometimes sparsely farinose on some surfaces, especially when young)
    • 6b. Sepals keeled on the abaxial surface, not conforming to the fruit, the calyx appearing pentagonal or star-shaped [Fig. 328]; stems, leaf blades, and sepals moderately to densely farinose (foliage sometimes ± glabrous in forms of C. album)

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 Show photos of:   Each photo represents one species in this genus.